Artificial selection for short and long attack latencies in wildMus musculus domesticus

Artificial selection for short and long attack latency levels in wild male Mus musculus over 11 generations was successful for short latencies. The realized heritability of 0.30 is comparable to those found in other selection studies on aggression. In part selection may have been for faster ontogenetic development of short attack latencies. Four attempts to select for longer attack latencies failed because the lines died out immediately or within two generations for unknown reasons. But neither the physical condition of the animals nor their behavior appeared to have been the cause. Female aggressiveness as measured in female-female encounters was not affected by the selection exerted on the males. This suggests that no genetic correlation exists between aggressiveness of males and females, confirming results of P. D. Ebert and J. S. Hyde [(1976).Behav. Genet.6:291–304] obtained in a selection experiment on aggression using females

A mouse is not just a mouse

In this paper we describe the existence and consequences of subspecific and individual variation in the genetic make-lip of house mice. The purpose is to illustrate forms of variation that are often neglected in discussions about animal care and experimental design. Towards this end different inbred mouse strains as well as genetically selected mouse lines are compared in relation to their ecological origin. Firstly, the behaviour of BALB/c, C57BL/6J and CBA mice is described in relation to different habitats. Furthermore, their aggression is compared, as measured by two paradigms. It appears that some inbred lines leg BALB/c and C57BL/6J) clearly show behaviour that reflects the functional adaptation to the natural habitats in which their ancestors lived. Other strains leg CBA) show a lack of such behavioural adaptation and their phenotypes appear to be very unstable over time. Secondly, two fundamentally different characters, both present in populations of wild house mice and under genetic control, ave described: on the one hand, active copers are characterized by aggressive behaviour; on the other hand, passive copers are reluctant to attack. The active, aggressive animals (manipulators) are well adapted to an invariant environment like their own territory, whereas the passive, non-aggressive copers (adjustors) are well adapted to a changing environment, eg when roaming. We discuss to what extent these coping styles are present in laboratory strains of mice. The major conclusion with regard to both phenomena is that individual and subspecific variation may have significant implications for experimental design and the welfare of the experimental animals

Studies on wild house mice. v: aggression in lines selected for attack latency and their y-chromosomal congenics

Congenic lines were made for the Y chromosome between aggressive and nonaggressive lines of house mice, which were previously established by artificial selection in wild mice for short attack latencies (SAL line) and long attack latencies (LAL line). The aggressiveness of the males in successive backcross generations of the congenic lines is reported. Results fit the hypothesis that the Y-chromosomal effect that is often found for aggression in house mice may be located on the pseudo-autosomal region of this chromosome

No evidence for a Y chromosomal effect on alternative behavioral strategies in mice

This study takes the first step toward testing a Y chromosomal effect on both aggression and thermoregulatory nest-building behavior in mouse lines either bidirectionally selected for short (SAL) and long (LAL) attack latency or high (HIGH) and low (LOW) nest-building behavior. Using reciprocal crosses between SAL and LAL, and between HIGH and LOW, we found no indications for Y chromosomal effects on thermoregulatory nest-building behavior. As for aggression, we confirmed earlier studies on SAL and LAL, i.e., the origin of the Y chromosome influences attack latency, i.e., aggression. However, we did not find indications for a Y chromosomal effect on aggression in the HIGH and LOW lines. Since aggression and nest-building behavior have been shown to be characteristic parameters of two fundamentally different behavioral strategies, the present data underline the improbability of Y chromosomal genes underlying the genetic architecture of alternative behavioral strategies

Employment Relationships in Terms of Wage Costs Optimization

Bakalářská práce se zaměřuje na problematiku pracovněprávních vztahů. V teoretické části jsou vymezeny základní pojmy pracovněprávních vztahů, které jsou dále využity v analytické části této práce. Analytická část se zabývá odměňováním zaměstnanců u konkrétního zaměstnavatele při nově zavedeném benefitu, který má za cíl zvýšit pravidelnou docházku zaměstnanců. Vyhodnocuje účinnost zavedeného opatření a obsahuje návrhy na zlepšení do budoucna.The Bachelor thesis focuses on the issue of labor relations. In the theoretical part are defined basic terms of labor relations, which are further applied in the analytical part of this thesis. The analytical part deals with the benefit for employees at the particular employer, when employer implemented new bonus, which its goal is to increase employee attendance system. Evaluated efficiency this established solution and includes suggestions for improvement in the future.

Y chromosomal and sex effects on the behavioral stress response in the defensive burying test in wild house mice

Genetically selected short attack latency (SAL) and long attack latency (LAL) male wild house mice behave differently in the defensive burying test. When challenged, SAL males respond actively with more time spent on defensive burying, whereas LAL males are more passive with more time remaining immobile. The first aim of this study was to find out whether the nonpairing part of the Y chromosome (Y(NPAR)) affects the behavioral stress response in this paradigm. Second, to determine if the differential behavioral profile found in males is also present in females, SAL and LAL females were tested. Third, nonattacking and attacking LAL males were compared. Five behavioral elements were recorded: defensive burying, immobility, rearing, grooming, and exploration. Males were first tested for attack latency. The results show that the Y(NPAR) influences defensive burying. However, the size of this effect is overshadowed by the background of the mice. Furthermore, although females differed from males, they tended to demonstrate the same behavioral profile as males. Nongenetic factors may also play a role, as attacking LAL males showed more defensive burying than nonattacking LAL males. (C) 1999 Elsevier Science Inc.</p